“Today, President Obama affirmed that for a people of many different faiths -- a people who are committed to the principle of religious freedom -- the way forward is always to be found through greater respect for the equal rights and human dignity of all," O'Malley said. "In Maryland, we agree."

"Ultimately, we all want the same thing for our children: to live in a loving, stable committed home protected equally under the law," O'Malley said.

The governor has undergone an "evolution" on the issue similar to that of Obama, only he arrived at a position of fully supporting same-sex marriage about a year earlier. When he first ran for governor in 2006, he expressed support for civil unions but after winning election did little to push the issue during his first term. In 2010, O'Malley expressed support for same-sex marriage in a campaign questionnaire from the Maryland Catholic Conference.

The next year, the governor voiced support for a same-sex marriage bill but did not make it a part of his legislative agenda. The measure failed. This year, he made the issue his own and won its passage by a narrow margin in the General Assembly. It still faces a likely challenge in a November referendum.

Obama told ABC's Robin Roberts Wednesday that "at a certain point I’ve just concluded that for me personally it is important for me to go ahead and affirm that I think same sex couples should be able to get married."